1 files changed, 186 insertions, 0 deletions
diff --git a/vendor/sebastian/recursion-context/src/Context.php b/vendor/sebastian/recursion-context/src/Context.php
new file mode 100644
index 000000000..87fe7b04f
--- /dev/null
+++ b/vendor/sebastian/recursion-context/src/Context.php
@@ -0,0 +1,186 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of the Recursion Context package.
+ *
+ * (c) Sebastian Bergmann <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\RecursionContext;
+
+use const PHP_INT_MAX;
+use const PHP_INT_MIN;
+use function array_pop;
+use function array_slice;
+use function count;
+use function is_array;
+use function is_object;
+use function random_int;
+use function spl_object_hash;
+use SplObjectStorage;
+
+/**
+ * A context containing previously processed arrays and objects
+ * when recursively processing a value.
+ */
+final class Context
+{
+    /**
+     * @var array[]
+     */
+    private $arrays;
+
+    /**
+     * @var SplObjectStorage
+     */
+    private $objects;
+
+    /**
+     * Initialises the context.
+     */
+    public function __construct()
+    {
+        $this->arrays  = [];
+        $this->objects = new SplObjectStorage;
+    }
+
+    /**
+     * @codeCoverageIgnore
+     */
+    public function __destruct()
+    {
+        foreach ($this->arrays as &$array) {
+            if (is_array($array)) {
+                array_pop($array);
+                array_pop($array);
+            }
+        }
+    }
+
+    /**
+     * Adds a value to the context.
+     *
+     * @param array|object $value the value to add
+     *
+     * @throws InvalidArgumentException Thrown if $value is not an array or object
+     *
+     * @return bool|int|string the ID of the stored value, either as a string or integer
+     *
+     * @psalm-template T
+     * @psalm-param T $value
+     * @param-out T $value
+     */
+    public function add(&$value)
+    {
+        if (is_array($value)) {
+            return $this->addArray($value);
+        }
+
+        if (is_object($value)) {
+            return $this->addObject($value);
+        }
+
+        throw new InvalidArgumentException(
+            'Only arrays and objects are supported'
+        );
+    }
+
+    /**
+     * Checks if the given value exists within the context.
+     *
+     * @param array|object $value the value to check
+     *
+     * @throws InvalidArgumentException Thrown if $value is not an array or object
+     *
+     * @return false|int|string the string or integer ID of the stored value if it has already been seen, or false if the value is not stored
+     *
+     * @psalm-template T
+     * @psalm-param T $value
+     * @param-out T $value
+     */
+    public function contains(&$value)
+    {
+        if (is_array($value)) {
+            return $this->containsArray($value);
+        }
+
+        if (is_object($value)) {
+            return $this->containsObject($value);
+        }
+
+        throw new InvalidArgumentException(
+            'Only arrays and objects are supported'
+        );
+    }
+
+    /**
+     * @return bool|int
+     */
+    private function addArray(array &$array)
+    {
+        $key = $this->containsArray($array);
+
+        if ($key !== false) {
+            return $key;
+        }
+
+        $key            = count($this->arrays);
+        $this->arrays[] = &$array;
+
+        if (!isset($array[PHP_INT_MAX]) && !isset($array[PHP_INT_MAX - 1])) {
+            $array[] = $key;
+            $array[] = $this->objects;
+        } else { /* cover the improbable case too */
+            do {
+                $key = random_int(PHP_INT_MIN, PHP_INT_MAX);
+            } while (isset($array[$key]));
+
+            $array[$key] = $key;
+
+            do {
+                $key = random_int(PHP_INT_MIN, PHP_INT_MAX);
+            } while (isset($array[$key]));
+
+            $array[$key] = $this->objects;
+        }
+
+        return $key;
+    }
+
+    /**
+     * @param object $object
+     */
+    private function addObject($object): string
+    {
+        if (!$this->objects->contains($object)) {
+            $this->objects->attach($object);
+        }
+
+        return spl_object_hash($object);
+    }
+
+    /**
+     * @return false|int
+     */
+    private function containsArray(array &$array)
+    {
+        $end = array_slice($array, -2);
+
+        return isset($end[1]) && $end[1] === $this->objects ? $end[0] : false;
+    }
+
+    /**
+     * @param object $value
+     *
+     * @return false|string
+     */
+    private function containsObject($value)
+    {
+        if ($this->objects->contains($value)) {
+            return spl_object_hash($value);
+        }
+
+        return false;
+    }
+}